Hello I got enough nerve to test this sub out in the pool I tested out the Dallas it is way better than I thought it would be!!!! I dove 6 feet with it before I lost radio but there were some dead spots. Though it works accross the pool without any problems at surface. Now the biggest flaw I see so far, is the steering props they are only two bladed and they don't steer it as good as I think it would with a three bladed prop. I am very impressed and this little sub and now I am bitten with the bug. Need to get busy with my PVC unit. I will test out the Chicago tomorrow. I noticed that they are on the same frequency I thought one was 40 megahertz and the other on 27 don't know. The last two digits on the FCC number is 27 So I am thinking they are 27 not 40 MHZ ... I don't know.. Well that is my thoughts on this better than I thought toy.. Tom .